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Arc Load Match (bleeding edge) OUCH!!
Hi Richard and All,
As you and Malcolm suspected, the "booster" coil idea has a problem. As I
held my little "wonder coil" in my hand, I too began to suspect that
something had gone wrong in the theoretical analysis.
The basic problem was a mathematical error on my part. The reactance of
5pF at 110kHz is 289k ohms. A matching inductor would have a value of
419mH not 418uH. I was off by a factor of 1000!
So, in order to get my dreamed of 30% increase in arc energy, I now need a
very large inductance. Such an inductor would be much larger than my 75mH
secondary. It would have substantial self capacitance, losses, etc. which
would easily destroy the effects I would need. Also, it would be rather
sensitive to variation in the 5pF arc capacitance which can vary
substantially.
The model does show that a perfect 418mH inductor would be wonderful.
However, there is no way to build the required device in the real world...
Oh well... lots more blood where that came from :-)
Terry
At 11:44 PM 10/22/98 -0400, you wrote:
snip...>
> Terry,
>
>The idea is laudable and worth a shot. The problem is that the extra coil
on most
>magnifiers is tuned in, sort of at the transmission line, from the driver. I
>always did this sort of unconsciously by varying the length of the line on
large
>units. (Lou Balint deserves the credit for sort of codifying this
effort). To
>withstand the tension and such from one of our magnifier's huge terminal
>capacities would be quite a feat of shielding and electrostatic field
control.
>
>The 12" long extra coil on maggey 11E is only 4 inches in diameter while its
>output terminal is 50" in diameter. I doubt seriously that a similar 4"
form for
>the 400uh "booster" coil could contain the energy found on the terminal of
this
>machine at 7KW.
>
>I'll have to dwell on this a bit.
>
>Richard Hull, TCBOR
>
>
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